<!DOCTYPE html>
<meta charset="UTF-8">
<style>
.parent {
  --length: 30px;
}
.target {
  --length: 10px;
  font-size: 20px;
}
</style>
<body>
<script src="../interpolation/resources/interpolation-test.js"></script>
<script>
CSS.registerProperty({
  name: '--length',
  syntax: '<length>',
  initialValue: '40px',
  inherits: false,
});

assertInterpolation({
  property: '--length',
  from: neutralKeyframe,
  to: '20px',
}, [
  {at: -0.3, is: '7px'},
  {at: 0, is: '10px'},
  {at: 0.5, is: '15px'},
  {at: 1, is: '20px'},
  {at: 1.5, is: '25px'},
]);

assertInterpolation({
  property: '--length',
  from: 'initial',
  to: '20px',
}, [
  {at: -0.3, is: '46px'},
  {at: 0, is: '40px'},
  {at: 0.5, is: '30px'},
  {at: 1, is: '20px'},
  {at: 1.5, is: '10px'},
]);

assertInterpolation({
  property: '--length',
  from: 'inherit',
  to: '20px',
}, [
  {at: -0.3, is: '33px'},
  {at: 0, is: '30px'},
  {at: 0.5, is: '25px'},
  {at: 1, is: '20px'},
  {at: 1.5, is: '15px'},
]);

assertInterpolation({
  property: '--length',
  from: 'unset',
  to: '20px',
}, [
  {at: -0.3, is: '46px'},
  {at: 0, is: '40px'},
  {at: 0.5, is: '30px'},
  {at: 1, is: '20px'},
  {at: 1.5, is: '10px'},
]);

assertInterpolation({
  property: '--length',
  from: '-10px',
  to: '10px',
}, [
  {at: -0.3, is: '-16px'},
  {at: 0, is: '-10px'},
  {at: 0.5, is: '0px'},
  {at: 1, is: '10px'},
  {at: 1.5, is: '20px'}
]);

assertInterpolation({
  property: '--length',
  from: '10em',
  to: '20em',
}, [
  {at: -0.3, is: '140px'},
  {at: 0, is: '200px'},
  {at: 0.5, is: '300px'},
  {at: 1, is: '400px'},
  {at: 1.5, is: '500px'}
]);

assertInterpolation({
  property: '--length',
  from: '10em',
  to: '100px',
}, [
  {at: -0.3, is: '230px'},
  {at: 0, is: '200px'},
  {at: 0.5, is: '150px'},
  {at: 1, is: '100px'},
  {at: 1.5, is: '50px'}
]);
</script>
</body>
